a. Field of the Invention
The present invention relates to tools which have a metal portion which is useful for sharpening other tools. More particularly, the invention relates to a tool for use in tuning ski bottoms and in sharpening ski edges, which tool utilizes multiple sharpening devices and guide means.
b. Discussion of the Prior Art
Downhill skiing has become a very popular activity, with millions of skiers using the ski slopes numerous times every ski season. As the popularity of the sport has increased, the quality and complexity of downhill skis has been increased.
Skis require constant maintenance in order for them to preserve or maintain a good degree of maneuverability and safety. Most present-day skis are constructed with longitudinal, bottom metal edges which are L-shaped in configuration and which extend along the side edges and the bottom surface adjacent the edge of the ski. These L-shaped edges are arranged so that their vertical side portions extend at least partially up the longitudinal side surfaces of the ski, and so that their horizontal bottom portions extend inwards towards one another along the bottom of the ski. The space on the bottom of the ski between the bottom metal portions is usually quite extensive in width, and is most often constructed of plastic, plastic-composite materials, or wood. It is current practice to normally apply a coating of wax to the bottom surface of the ski in order to reduce or control friction between the ski and the snow, and also as a form of protection to the bottom of the ski. After repeated use of such a ski, the metal edges tend to become dull and often become nicked, and the ski bottom becomes scratched and may also assume a concave contour along its transverse cross-section. Were it not for the ability to "tune" or recondition the bottom and edges of the ski, the user would be burdened by decreased and decreasing performance, evidenced, for example, by reduced turning ability and downhill speed. In addition, the bottom would eventually require major reconditioning and the metal edges would require complete replacement from time to time.
Ski reconditioning techniques and tools currently exist. However, such tools in the hands of an experienced user consume considerable amounts of time, and often require special fixtures for holding the skis in place during such reconditioning. Currently, ski reconditioning most often requires the use of many separate tools and materials, such as files, cutters, routers, planes, cork, meltable plastic, and wax. Such tools and materials in the hands of the inexperienced user may result in unsatisfactory tuning, or even in permanent damage to the ski and potential danger to the ski user.
There are on the market at the present time, and there have been designed and patented in the past, a number of ski conditioning tools, including files or cutters which may be slid along the side surface of a ski's metal edges, and which provide the necessary support to effect a substantially vertical cutting or filing operation in order to sharpen the metal side edges. Such tools have also included separately or in combination, scraper bars, strips or files which ride on the bottom surfaces of the ski and the bottom surfaces of the L-shaped metal runners with the intention of leveling the bottom of the ski while simultaneously sharpening the bottom portion of the metal edges.
Several ski repair and tuning devices are disclosed by the prior art. U.S. Pat. No. 3,670,601 discloses a ski sharpening device which provides a flat platform for a portion of the skis with a file positioned at right angles to the platform. While this device provides some degree of assistance in maintaining the edge of the file perpendicular to the edge of the ski during sharpening, it fails to provide any means for tuning the bottom of the ski or for removing burrs from the metal edges. U.S. Pat. No. 3,834,250 discloses a method and device for tuning a pair of skis with a tuning device which incorporates side and bottom edge files and a scraping tool, utilized in conjunction with a unit for holding a pair of skis in a selected position. U.S. Pat. No. 3,875,825 discloses a device for sharpening the edges of a ski while smoothing its bottom. The device of this latter patent includes a central well portion which carries a flat file which can fit over the bottom of the ski. It also includes a resiliently mounted edge file in opposed sidewalls of the well. This causes the edge file blades to be resiliently urged against the edges of the metal strip at the bottom of a ski. In this latter patent the resilient means for urging the files against the edges of the skis are taught to be of the coil spring type which urge the files against the metal edges with varying amounts of force, depending upon the condition of the spring and the amount of expansion or compaction of the spring.
U.S. Pat. No. 3,934,287 discloses a combined ski maintenance tool which carries a flat file in one portion, a scraping blade in another portion, and a cork smoothing block in yet another portion. This tool allows the convenient selection of each portion as it is required for use in the tuning and maintenance of a ski. The tool of this latter reference also provides means for maintaining the file flat or perpendicular, as required for use in scraping the bottom of the ski or filing the edge of the ski. The degree of pressure applied during edge filing is controlled by the operator. U.S. Pat. No. 4,060,013 discloses a tool adapted for renovating or conditioning skis by sharpening the bottom and side surfaces, which tool includes an elongated body having a pair of spaced apart shaving strips extending along its bottom side and a pair of shaving blocks near its opposite end, which shaving blocks are spaced apart a greater distance than the maximum width of any ski. This device is hand operated so that the operator controls the degree of pressure which is applied to the edges during sharpening.
Such ski conditioning tools have not proven altogether satisfactory, with the principal limitation being the necessity of using great care and skill in the application of filing or cutting pressure in order to prevent localized digging or gouging of the bottom or edges of the ski by the files, cutter or scrapers. As discussed above, some such tools have taken care of the exposed side surfaces of the overhanging vertical part of the metal edge, while others take care of the bottom surface of the ski. A few such tools have been intended to perform both functions simultaneously. Nevertheless, all of them require special skills, or necessitate special fixtures (other than a vise) for holding the skis stationary while operating the tools, or otherwise put their users to a demanding task in the proper use of the tools. Finally, none of these known tools is designed to operate to automatically apply constant pressure to edge sharpening tools on opposite side surfaces of the metal edges of the skis.